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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Enhancing Lifetime and Reducing Costs for Fish Diversion Netting Structures (Abstract)

This effort will focus on technology transfer and commercialization of antifouling coatings with an enthusiastic and engaged industrial team. Environmental requirements and operational demands call for a nontoxic coating/paint to prevent fouling on fish passage guidance netting at hydropower facilities. For example, one netting customer estimated the capital cost for compliance at $\$12$ million to $\$15$ million. This project will build partnerships between PNNL and private companies to optimize, demonstrate, mature, and commercialize a novel PNNL-developed technology that addresses this critical coating need of the hydropower industry. This effort will support modification of existing coatings for application to flexible netting structures. Industrial partners include commercial coating development specialist (Lorama), hydrophobic material manufacturer and paint developer (Dry Surface Technologies), aquatic applications specialists (Prometheus Innovations and River Connectivity Systems), and hydropower netting producer (Pacific Netting Products). Engagement with the U.S. Army Corps of Engineers (USACE) and Bureau of Reclamation (BOR), two hydropower operators, throughout the project will provide expertise and field test sites that will provide crucial proof of real-world performance data (additional details provided in Teaming section). Taylor Shellfish Farms will provide organisms and fouling expertise as well as a perspective of potential broader impacts for the blue economy. Sample netting will demonstrate performance in a range of environments for key hydropower applications. PNNL will work with industrial partners to overcome commercialization barriers as well as resolving any manufacturing or regulatory issues. This Phase 1 effort is focused on technology optimization for application to fish passage guidance netting and technology validation as verified by independent testing (through USACE, BOR, Taylor Shellfish and Prometheus Innovations). Through this effort, SLIC will be demonstrated for netting applications at technology readiness level (TRL) 5. The field test data will allow optimization of SLIC formulation and performance which is key to enabling technology transfer of a mature proven technology to industry and production of a viable commercial product specifically focused for hydropower needs.

13 HYDRO ENERGY↗
DOE OSTI2026

Making an s1G Self-Preserving Environmental DNA (eDNA) Filter from Sustainable Materials

Environmental DNA (eDNA) sampling of aquatic environments is a powerful new tool for resource managers to use in detecting the presence of rare and endangered species. The use of eDNA for species detection is quickly becoming an industry-standard methodology in environmental science, and the technology sector is moving quickly to create purpose-built tools for eDNA sampling. Smith-Root, Inc. pioneered the new technology of self-preserving eDNA filters that automatically preserve the DNA captured on filters by desiccating the internal filter membrane. This capability saves the sampling technician significant time in the field and drastically reduces the potential for sample contamination. One main constraint of this new technology, however, is the necessity of single-use plastics for eDNA sampling. Single-use designs are employed because sampling equipment must be devoid of potential contaminating DNA, and the time required to sterilize equipment is often not cost-effective for practitioners. Thus, this technology is creating a significant new source of plastic waste—something that eDNA practitioners, and society, would like to avoid. This project explores the use of alternative bio based polymers and composites as replacements for incumbent industrial standards for eDNA filtration systems, with an emphasis on ease of processing and biodegradable options. 8 candidate materials, 3 for the top filter housing and 5 for the bottom filter housing, were investigated to replace incumbent housing materials. Of the 8 candidates, 2 materials were identified for future investigation which met performance requirements, were bio-based and could potentially offer better disposal options like soil degradation or composting, features sought by the customers of these products. The top housing candidate, material 1, has comparable performance to the incumbent material and equally manufacturable. The bottom housing candidate, material 6, improved desiccation performance by 81% after 1 hour in comparison to the incumbent material, is 100% bio-based, compostable and can be sourced domestically throughout the U.S.A.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Process innovations to enable viable enzymatic poly(ethylene terephthalate) recycling

Enzymatic depolymerization of poly(ethylene terephthalate) (PET) has received considerable attention for closed-loop polyester recycling. However, current approaches for enzymatic PET recycling face challenges to achieve commercial viability with lower environmental impacts compared with virgin polyester manufacturing. Here, in this study, we present multiple process innovations for enzymatic PET recycling that enable economic and environmental feasibility. We show that substrate amorphization through extrusion and quenching is energy-efficient and enables near-quantitative enzymatic conversion in 50 h. Using ammonium hydroxide for pH control and thermolysis of the isolated diammonium terephthalate salt reduces the acid and base consumption by >99%, lowering annual operating expenses by 74%. Fed-batch processing increased ethylene glycol concentration, leading to a 65% reduction in energy consumption for ethylene glycol recovery. These improvements were modeled in an optimal process, with recycled PET estimated to be US$\$$1.51 kg -1 relative to US domestic virgin PET at US$\$$1.87 kg -1 and eliminating key life cycle obstacles to scale this technology.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Phototunable Lignin Plastics to Enable Recyclability

The accumulation of non-degradable petrochemical plastics imposes a significant threat to the environment and ecosystems. We addressed this challenge by designing a new type of phototunable plastics based on the unique lignin chemistry to enable readily end-life recycling. The advanced material design leveraged the efficient photocatalytic lignin depolymerization by ZnO nanoparticles to build lignin-polymethyl methacrylate (PMMA)-ZnO blends. We first demonstrated the highly effective phototunable lignin depolymerization in the complex polymer blend matrix and explored the molecular mechanisms. The technical barriers of mechanical property and recycling processing were then addressed by a new blend design with lignin core grafted with PMMA polymer. The new process has resulted in a new type of PMMA-g-lignin blend, which significantly improved the mechanical properties, making it comparable to PMMA alone. More importantly, the mechanical properties of the UV-treated blend decreased drastically in the new design, whereas the properties did not reduce in the non-grafted blends upon UV exposure. The results highlighted that the new blend design based on graftization maximized the impact of lignin depolymerization on blend structure and recyclability. Based on the results, we developed a process integrating UV and alkaline treatments to recycle PMMA for plastics and fractionated lignin for bioconversion or other applications in the new phototunable plastics.

36 MATERIALS SCIENCE↗
DOE OSTI2020

BdGT43B2 functions in xylan biosynthesis and is essential for seedling survival in Brachypodium distachyon

Abstract Xylan is the predominant hemicellulose in the primary cell walls of grasses, but its synthesis and interactions with other wall polysaccharides are complex and incompletely understood. To probe xylan biosynthesis, we generated CRISPR/Cas9 knockout and amiRNA knockdown lines of BdGT43B2 , an ortholog of the wheat TaGT43‐4 xylan synthase scaffolding protein in the IRX14 clade, in Brachypodium distachyon . Knockout of BdGT43B2 caused stunting and premature death in Brachypodium seedlings. Immunofluorescence labeling of xylans was greatly reduced in homozygous knockout BdGT43B2 mutants, whereas cellulose labeling was unchanged or slightly increased. Biochemical analysis showed reductions in digestible xylan in knockout mutant walls, and cell size was smaller in knockout leaves. BdGT43B2 knockdown plants appeared morphologically normal as adults, but showed slight reductions in seedling growth and small decreases in xylose content in isolated cell walls. Immunofluorescence labeling of xylan and cellulose staining was both reduced in BdGT43B2 knockdown plants. Together, these data indicate that BdGT43B2 functions in the synthesis of a form of xylan that is required for seedling growth and survival in Brachypodium distachyon .

36 MATERIALS SCIENCE↗
DOE OSTI2023

Cost and Life Cycle Analysis for Deep CO 2 Emissions Reduction for Steel Making: Direct Reduced Iron Technologies

Among heavy industrial sectors worldwide, the steel industry ranks first in carbon dioxide (CO 2 ) emissions. Technologies that produce direct reduced iron (DRI) enable the industry to reduce emissions or even approach net‐zero CO 2 emissions for steel production. Herein, comprehensive cradle‐to‐gate (CTG) life cycle analysis (LCA) and techno‐economic analysis (TEA) are used to evaluate the CO 2 emissions of three DRI technologies. Compared to the baseline of blast furnace and basic oxygen furnace (BF–BOF) technology for steel making, using natural gas (NG) to produce DRI has the potential to reduce CTG CO 2 emissions by 33%. When 83% or 100% renewable H 2 is used for DRI production, DRI technologies can potentially reduce CO 2 emissions by 57% and 67%, respectively, compared to baseline BF–BOF technology. However, the renewable H 2 application for DRI increases the levelized cost of steel (LCOS). When renewable natural gas (RNG) and clean electricity are used for steel production, the CTG CO 2 emissions of all the DRI technologies can potentially be reduced by more than 90% compared to the baseline BF–BOF technology, although the LCOS depends largely on the cost of RNG and clean electricity.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2021

Encapsulation of highly viscous CO 2 capture solvents for enhanced capture kinetics: Modeling investigation of mass transfer mechanisms

The encapsulation of highly viscous liquid-like Nanoparticle Organic Hybrid Materials (NOHMs) inside a gas permeable polymer to form SIPs (Solvent Impregnated Polymers) significantly enhanced the CO 2 capture kinetics of NOHMs, leading to a remarkable 50-fold increase in CO 2 flux compared to the neat NOHMs. To understand the mechanism for enhanced CO 2 mass transfer within these hybrid materials, kinetic modeling of CO 2 uptake into SIPs containing polyethylenimine functionalized NOHMs, denoted NPEI-SIP, was conducted. CO 2 mass transfer into NPEI-SIP films was found to conform, both qualitatively and quantitatively, with a diffusion-controlled moving front model. The diffusion-controlled model was also used to simulate CO 2 uptake within a fixed bed containing polydisperse NPEI-SIP particles, and this model accurately predicted experimentally measured breakthrough curves at 25 °C and 50 °C. The 50-fold increase in gas flux was shown to be a consequence of the very large CO 2 permeability within the polymer–solvent composite. Furthermore, the increase in gas flux is also dependent on the diffusion–reaction regime in which the chemical solvent operates, and the largest improvement will occur when immobilizing solvents, such as NOHMs, which operate in the instantaneous-reaction regime. The CO 2 capacity (~3 mol CO 2 /kg) and saturation time (~5 min) of 430 μm SIP particles were comparable to popular CO 2 chemisorption materials such as amine grafted silicates, in spite of the slow kinetics of NOHM-I-PEI in liquid form (CO 2 saturation time ~24 h for a 1 mm thin film).

36 MATERIALS SCIENCE↗
DOE OSTI2024

The damage Mechanics challenge Results: Participant predictions compared with experiment

In this article, We present results from a recent exercise where participating organizations were asked to provide model-based blind predictions of damage evolution in 3D-printed geomaterial analogue test articles. Participants were provided with a range of data characterizing both the undamaged state (e.g., ultrasonic measurements) and damage evolution (e.g., 3-point bending, unconfined compression, and Brazilian testing) of the material. In this paper, we focus on comparisons between the participants’ predictions and the previously secret challenge problem experimental observations. We present valuable lessons learned for the application of numerical methods to deformation and failure in brittle-ductile materials. The exercise also enables us to identify which specific types of calibration data were of most utility to the participants in developing their predictions. Further, we identify additional data that would have been useful for participants to improve the confidence of their predictions. Consequently, this work improves our understanding of how to better characterize a material to enable more accurate prediction of damage and failure propagation in natural and engineered brittle-ductile materials.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Landfilled coal ash for carbon dioxide capture and its potential as a geopolymer binder for hazardous waste remediation

In this report, the legacy of global fossil fuel usage is not just the increase in global warming due to CO 2 production, but also the billions of tons of toxic coal ash disposed in landfills. This investigation evaluates the merits of using high-calcium landfilled coal fly ash of different disposal durations and granulated blast furnace (GBF) slag as primary raw materials for production of a new class of geopolymer binder. Processing of landfilled coal fly ash, GBF slag and supplementary raw materials into a geopolymer binder was accomplished by a simple, scalable milling process in the absence of heating under a carbon dioxide environment. The resultant geopolymer cement binders were tested for carbon dioxide uptake, compressive strength, and heavy metal stabilization. The geopolymer binder demonstrated a desired balance of carbon dioxide uptake, strength and safety. These results also indicate that the performance of the geopolymer binder depends on the landfill disposal age of the coal fly ash.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2025

A review of quantum imaging methods and enabling technologies

The field of quantum imaging has recently seen an explosion of new methods and techniques. At the heart of most quantum imaging approaches are three enabling technologies: the source of the quantum light, the detectors that turn sensing into imaging, and the method by which the quantum nature of light is leveraged to improve the desired measurement. This review addresses the dominant and emerging technologies in each of these components as well as details concerning the implementations of various quantum imaging methods.

36 MATERIALS SCIENCE↗
DOE OSTI2021

United States plastics: Large flows, short lifetimes, and negligible recycling

Given increasing concerns for the marine environment and human health, as well as trade restrictions from Asian countries, plastics have become a great challenge for the United States. This study addresses the seven commonly used plastics: low-density polyethylene/linear low-density polyethylene, high-density polyethylene, polyethylene terephthalate (PET), polypropylene, polystyrene, polyvinyl chloride, and other plastics. Material flows of the seven polymers were tracked from production into fabrication, manufacturing, flow into use, waste management, and recycling in the United States in 2015. Low- and high-density polyethylene and polypropylene were found to be the largest in both production and product manufacture. More than 88% of the plastics went into three end-use sectors: Packaging, Consumer and Institutional Products, and Building and Construction. In-use lifetimes across the plastics are generally short. Virgin plastics were mainly exported, while intermediate plastic products were largely imported. The actual end-of-life recycling rate of the plastics as a group was no more than 6.2%, with PET and the polyethylene family the most recycled. Here, the high yearly plastic throughput and low recycling rate pose a serious challenge to the sustainability goals of the United States and is in stark contrast to the vision of a circular economy of plastics.

02 PETROLEUM↗
DOE OSTI2020

First-Principles Modeling of Sodium Ion and Water Intercalation into Titanium Disulfide Interlayers for Water Desalination

Recent experiments revealed the possibility of using titanium disulfide (TiS 2 ) as the cathode material in capacitive deionization (CDI) devices for water desalination. Although it performed stably up to 70 cycles with a salt removal capacity of 14 mg/g (corresponding to a sodium ion removal capacity of 35.8 mg/g) at high molar concentration (600 mM NaCl), the maximum capacity of TiS 2 as a CDI electrode was much lower (~70 mAh/g) than as a supercapacitor (239 mAh/g). Understanding why the ion capacities of these two configurations of the same material differ will entail elucidating detailed charge/discharge mechanisms at the atomic scale. Here, we present density functional theory simulations of sodium intercalation into TiS 2 interlayers in order to gain such understanding. We systematically investigated TiS 2 stacking patterns and ion intercalation sites, energetics of the intercalated compounds, and phase transformation during sodium intercalation. The calculated structural evolution and capacitance–voltage curve agree quite well with previous measurements. We conclude that the different maximum capacities of TiS 2 measured in aqueous and dry environments originate from weaker interlayer interactions with respect to shear strain after ~33% intercalation of Na + –H 2 O pairs, which is detrimental to the mechanical stability of TiS 2 . In conclusion, this study sheds light on the underlying mechanisms of ion intercalation into layered materials and contributes to understanding requirements for future design and optimization of CDI electrode materials for water desalination.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Electrolyte-Guided Design of Electroreductive CO Coupling on Copper Surfaces

Engineering the interfacial distribution of electrolytic ions can aid in modulating the electrocatalyst performance and efficiency. Using a hybrid quantum-classical modeling approach, we describe how predictive tuning of the solution microenvironment on copper can enhance the efficiency of CO 2 reduction (CO 2 R) to C 2 products. We elucidate how competing electrolyte constituents in mixed electrolyte solutions stimulate restructuring of the electrochemical double layer (EDL) and stabilize the OCCO* dimer (* denotes surface adsorbed), with predictions validated in flow reactors using copper gas diffusion electrodes (Cu-GDEs). Furthermore, our findings highlight how molecular-scale electrolyte engineering with informed models of the EDL can be leveraged to tailor CO 2 R activity and selectivity toward C 2 products.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Selective Removal of Barium and Hardness Ions from Brackish Water with Chemically Enhanced Electrodialysis

The use of a nonconventional water resource for energy and industrial applications often requires extraction of low-level undesirable ions from matrices of benign dominant ions. In this study, the selective extraction of Ba 2+ and Mg 2+ from synthetic brine solutions was evaluated using strong acid cation-exchange membranes modified with the surface deposition of macrocyclic molecules including crown ethers and calixarenes. Compared to the bare membrane, vinylbenzo-18-crown-6 (VB18C6) and calix[4]arene-amended membranes showed increased selectivity for Ba 2+ and Mg 2+ with respect to the dominant ion (Na + ) by up to fourfolds, with the calix[4]arene-modified membrane achieving more selective separation than VB18C6. Optimal selectivity was achieved at a moderate-to-high current density (3.1–6.3 mA/cm 2 ), which was attributed to the alleviation of transport limitation in the boundary layer by the surface modification. Amendment of a calix[4]arene derivative with a crown-6 “boot strap” and two carboxylic groups resulted in reduced selectivity due to the formation of strong complexes with divalent ions. Furthermore, these results show that surface deposition of ion sequestrants can be a versatile approach to improve the membrane’s selectivity; however, the performance is sensitive to feed water salinity, current loading, and the macrocycle-ion chemistry, where there is a trade-off between ion affinity and mobility.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Chemical Modifications of Ag Catalyst Surfaces with Imidazolium Ionomers Modulate H 2 Evolution Rates during Electrochemical CO 2 Reduction

Bridging polymer design with catalyst surface science is a promising direction for tuning and optimizing electrochemical reactors that could impact long-term goals in energy and sustainability. Particularly, the interaction between inorganic catalyst surfaces and organic-based ionomers provides an avenue to both steer reaction selectivity and promote activity. In this work, we studied the role of imidazolium-based ionomers for electrocatalytic CO 2 reduction to CO (CO 2 R) on Ag surfaces and found that they produce no effect on CO 2 R activity yet strongly promote the competing hydrogen evolution reaction (HER). By examining the dependence of HER and CO 2 R rates on concentrations of CO 2 and HCO 3 –, we developed a kinetic model that attributes HER promotion to intrinsic promotion of HCO 3 – reduction by imidazolium ionomers. We also show that varying the ionomer structure by changing substituents on the imidazolium ring modulates the HER promotion. This ionomer-structure dependence was analyzed via Taft steric parameters and density functional theory calculations, which suggest that steric bulk from functionalities on the imidazolium ring reduces access of the ionomer to both HCO 3 – and the Ag surface, thus limiting the promotional effect. Our results help develop design rules for ionomer–catalyst interactions in CO 2 R and motivate further work into precisely uncovering the interplay between primary and secondary coordination in determining electrocatalytic behavior.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Upcycling waste polystyrene to adipic acid through a hybrid chemical and biological process

Oxidative catalytic depolymerization of polystyrene (PS) can produce benzoic acid, but the annual consumption of benzoic acid is ~40 times lower than PS. For this catalytic oxidation method to be a viable means to manage PS waste, benzoic acid should be converted to higher-volume chemicals. We demonstrate a hybrid chemical and biological process that uses PS as feedstock for production of adipic acid, a high-volume co-monomer for nylon 6,6 via benzoic acid. Mn/Br co-catalyzed autoxidation of PS to benzoic acid proceeds with a yield of up to 94% in a solvent mixture of benzoic acid and water. The PS-derived benzoic acid undergoes bioconversion at near-quantitative yield to muconic acid, which is readily converted to adipic acid through catalytic hydrogenation. Process modeling, techno-economic analysis, and life cycle assessment estimate an adipic acid minimum selling price of $3.18/kg, with a 61% decrease in greenhouse gas emissions relative to production from fossil fuels.

09 BIOMASS FUELS↗
DOE OSTI2024

Rapid biodegradation of microplastics generated from bio-based thermoplastic polyurethane

The accumulation of microplastics in various ecosystems has now been well documented and recent evidence suggests detrimental effects on various biological processes due to this pollution. Accumulation of microplastics in the natural environment is ultimately due to the chemical nature of widely used petroleum-based plastic polymers, which typically are inaccessible to biological processing. One way to mitigate this crisis is adoption of plastics that biodegrade if released into natural environments. In this work, we generated microplastic particles from a bio-based, biodegradable thermoplastic polyurethane (TPU-FC1) and demonstrated their rapid biodegradation via direct visualization and respirometry. Furthermore, we isolated multiple bacterial strains capable of using TPU-FC1 as a sole carbon source and characterized their depolymerization products. Finally, to visualize biodegradation of TPU materials as real-world products, we generated TPU-coated cotton fabric and an injection molded phone case and documented biodegradation by direct visualization and scanning electron microscopy (SEM), both of which indicated clear structural degradation of these materials and significant biofilm formation.

09 BIOMASS FUELS↗
DOE OSTI2021

On-device lead absorbing tapes for sustainable perovskite solar cells

Perovskite solar cells are a promising technology that could facilitate and accelerate the energy transition to a sustainable future. However, the toxicity of Pb remains one of the obstacles impeding their commercialization. Here we apply on-device tapes to absorb leaked lead from damaged devices. Furthermore, our chemical approach can capture over 99.9% of leakage without compromising the performance and operation.

14 SOLAR ENERGY↗